Gradient on a topographic map represents the steepness of a slope. It is calculated by determining the difference in elevation between two points (the rise) and dividing it by the horizontal distance between those points on the map (the run). This value is then typically expressed as a ratio, a percentage, or in degrees. For example, if the elevation changes by 100 meters over a horizontal distance of 1000 meters, the gradient is 100/1000, or 1/10, often expressed as a 10% slope.
Understanding slope steepness is fundamental in various fields, including civil engineering, environmental science, and urban planning. Assessing this characteristic allows for informed decisions regarding construction feasibility, risk assessment for landslides or erosion, and optimal land use. Historically, early surveyors developed techniques for determining slope using simple tools, laying the foundation for the more precise methods used with modern topographic maps.
